1. Field of Invention
This invention relates to a mixer and, in particular, to a mixer providing high shear mixing of pasty, semi-solid materials.
2. Brief Statement Of The Prior Art
High shear mixers and blenders have been provided with sets of rotating and stationary blades. U.S. Pat. No. 3,709,664 discloses such an arrangement in which the stator blades are secured to the inner walls of the vessel. Household egg beaters are an illustration of portable mixers having stator blades closely positioned to propeller blades, such as those shown in U.S. Pat. Nos. 2,121,918 and 2,149,104. Household blenders also have been provided with high speed rotating blades in close proximity to sets of stator blades, such as in U.S. Pat. Nos. 3,499,633 and 3,197,181. The stator blades can also be rotated in an opposite rotational direction such as in U.S. Pat. No. 2,231,926 which shows counter-rotating blades or U.S. Pat. No. 4,190,371 which discloses a rotor driven at high rotational speed and a stator driven in the same direction but at much lower rotational speeds.
All of the aforementioned devices are relatively complex and are intended for very specific mixing or blending applications. Chunks of material or large particles and the like can become jammed between the rotor and stator blades and none of the devices have provisions for unloading these obstructions without removing, and in many cases dismantling, the mixing assembly.